A biodegradable carboxymethyl cellulose-based bioplastic for excellent electromagnetic interference shielding and mechanical properties

Sustainable alternatives with enhanced performance have attracted a great deal of research attention in response to the growing environmental and energy problems posed by petroleum-based plastics. However, the mechanical strength, water resistance, and functional properties of conventional bioplastics are occasionally restricted, limiting their utility. In this work, we describe a versatile cellulose-based bioplastic created through combining citric acid as a cross-linker and Ketjen black as a conductive filler with a carboxymethyl cellulose matrix. The optimized composite exhibits outstanding mechanical properties, including a tensile strength of 51.31 MPa and an elongation at break of 50.24%, as well as considerable electrical conductivity of 76.15 S/m, and a notable electromagnetic interference shielding effectiveness of 22.71 dB at a thickness of 0.19 mm. Its environmental compatibility was validated through soil degradation tests, confirming 100% biodegradability within 100 days with no observed effects on plant development. This study offers significant potential for flexible electronics and sustainable packaging by providing an environmentally friendly and scalable technique for designing high-performance multifunctional bioplastics.